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    <title>ShellCheck: SC2177 – `time` is undefined for compound commands, use `time sh -c` instead.</title>
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    <h1>SC2177 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2177">See this page on GitHub</a>
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    <h2
id="time-is-undefined-for-compound-commands-use-time-sh--c-instead"><code>time</code>
is undefined for compound commands, use <code>time sh -c</code>
instead.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2177.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">time</span> for i in <span class="pp">*</span>.bmp<span class="kw">;</span> <span class="cf">do</span> <span class="ex">convert</span> <span class="st">&quot;</span><span class="va">$i</span><span class="st">&quot;</span> <span class="st">&quot;</span><span class="va">$i</span><span class="st">.png&quot;</span><span class="kw">;</span> <span class="cf">done</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2177.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="bu">time</span> sh <span class="at">-c</span> <span class="st">&#39;for i in *.bmp; do convert &quot;$i&quot; &quot;$i.png&quot;; done&#39;</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p><code>time</code> is only defined for Simple Commands <a
href="http://pubs.opengroup.org/onlinepubs/9699919799/utilities/time.html">by
POSIX</a>. Timing loops, command groups and similar is not.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None. If you use a shell that supports this (e.g. bash, ksh), specify
this shell in the shebang.</p>
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